An opening is provided at a lower front of a vehicle to feed air to a radiator or the like, and thus overheating of an engine is suppressed.
However, if the opening is opened at all times, there is a concern that aerodynamic performance of the vehicle is reduced. Additionally, a temperature in an engine room hardly rises at the time of warming-up, and thus fuel efficiency deteriorates. In addition, fuel efficiency deteriorates due to excessive cooling of the engine at high-speed running.
Thus, techniques such as a Patent Literatures 1 and 2 in which a shutter device including fins, which is configured to open and close an opening thereof as necessary, is provided to improve aerodynamic performance or fuel efficiency, are known.